The state electorate of Giles has an approximate area of 494,000 km².

It is comprised of 44 suburbs including Amata, Andamooka, Backy Point, Bungeroo, Cowleds Landing, Douglas Point, Douglas Point South, Glendambo, Iron Baron, Iron Knob, Iwantja, Kalka, Kaltjiti, Kanpi, Katunga Station, Kimba, Kingoonya, Marla, Mimili, Murninnie Beach, Murputja, Narlaby, Nyapari, Oak Valley and Pimba plus parts of another 3 suburbs.

It is comprised of 118 localities including Anangu Pitjantjatjara Yankunytjatjara, Andamooka Station, Arckaringa, Arcoona, Arkaba, Ash, Ayers Range South, Barna, Barndioota, Batchelor, Billa Kalina, Bon Bon, Boolcunda, Bosworth, Buckleboo, Bulgunnia, Caralue, Castine, Chundaria, Commonwealth Hill, Coober Pedy, Coondambo, Cooyerdoo, Corrobinnie and Cortlinye plus parts of another 38 localities.

It is comprised of the councils of Anangu Pitjantjatjara Yankunytjatjara, Coober Pedy District, Kimba District, Maralinga Tjatjura, Municipal Of Roxby Downs, The City Of Whyalla, The Flinders Ranges and Uia Whyalla plus parts of Pastoral.

It is surrounded by the state electorates of Eyre, Flinders, Kalgoorlie, Namatjira and Stuart.

It is within the federal electorate of Grey.